docs: 中性化 README 与代码注释中的第三方客户端引用

- README.md / README_EN.md：桌面 GUI 段落的第三方客户端类比改为中性的「托盘式桌面客户端」，功能说明不变
- cmd/gui 注释、internal/provider 注释：代理示例改为中性的本地 HTTP 代理表述
- internal/lua/plugins/channels.lua、internal/lua/vm.go：注释措辞中性化

仅文案与注释调整，无任何逻辑变更。

internal/lua/plugins/channels.lua

@@ -7793,7 +7793,7 @@ plugin.http = {
 
 -- set_endpoints：改写某平台的端点声明（device.code_url/token_url、checkin.url、
 -- base_url）。两个用途：
--- 1. 运维把某渠道指向自建代理/镜像（厂商被墙、企业出口、审计要求）
+-- 1. 运维把某渠道指向自建代理/镜像（网络出口受限、企业出口、审计要求）
 -- 2. 测试把端点指到假上游，行为测试才能不打真厂商
 -- 只允许改已知字段，未知键拒绝 —— 端点声明是协议形状的一部分，静默加字段
 -- 会破坏后续逻辑对形状的假设。

internal/lua/vm.go

@@ -41,7 +41,7 @@ import (
 var bundledAdapters embed.FS
 
 // adapterGlobal is the reserved global holding the adapter table after the
-// worker boots the script. A reserved name avoids clashing with user code.
+// worker boots the script. A reserved name avoids conflicting with user code.
 const adapterGlobal = "__llmsproxy_adapter"
 
 type APIAdapter struct {

internal/provider/provider.go

@@ -26,9 +26,9 @@ import (
 )
 
 // proxyFor picks the transport proxy for one source. An explicit per-source
-// proxy_url wins (e.g. clash on 127.0.0.1:7890 for a geo-blocked upstream);
-// otherwise fall back to the process-wide env proxy, which is direct by
-// default.
+// proxy_url wins (e.g. a local HTTP proxy on 127.0.0.1:7890 for an upstream
+// that is only reachable through it); otherwise fall back to the
+// process-wide env proxy, which is direct by default.
 func proxyFor(cfg config.Source) func(*http.Request) (*url.URL, error) {
 	if cfg.ProxyURL != "" {
 		proxyURL, err := url.Parse(cfg.ProxyURL)
@@ -403,9 +403,10 @@ func New(cfg config.Source, vm *lua.VM) *Provider {
 	// Shared transport: ResponseHeaderTimeout bounds how long we wait for the
 	// first response byte (applies to both paths); the stream client has no
 	// client-level Timeout so the SSE body can run past the header timeout.
-	// A per-source ProxyURL (e.g. clash on 127.0.0.1:7890) overrides the
-	// process-wide env proxy for upstreams that are geo/IP-blocked; sources
-	// without one keep http.ProxyFromEnvironment (direct by default).
+	// A per-source ProxyURL (e.g. a local HTTP proxy on 127.0.0.1:7890)
+	// overrides the process-wide env proxy for upstreams that need an explicit
+	// egress path; sources without one keep http.ProxyFromEnvironment (direct
+	// by default).
 	tr := &http.Transport{
 		Proxy:                 proxyFor(cfg),
 		DialContext:           (&net.Dialer{Timeout: 30 * time.Second, KeepAlive: 30 * time.Second}).DialContext,